In the current state of the art, there are several machines devoted to an extensive range of operations involved in the various processes related to handling and processing of almonds and other similar dried fruit. More specifically, peeling machines are designed for peeling and re-peeling of almonds, in which almonds, after being peeled and conditioned, follow a pre-determined course inside the machine to be subjected to some type of superficial friction. The friction determines the peeling of the nut skin and the collection of the skin in appropriate containers, which typically attract the skin due to a current of air or a similar procedure.
One of such known almond peeling devices is described in ES 200902283. This patent describes a peeling machine in which the skin peeling function is implemented by means of one or more pairs of rollers, which are vertically overlapping, each pair having an adjustable separation, which determine as a whole a central vertical plane for dropping almonds between the rollers. The sliding effect implemented by the rollers on the surface of almonds due to the difference in the rotating speed of each pair the rollers determines the peeling of the skin. The distance between rollers may vary, and, for that purpose, the machine has a hand wheel, which through a shaft or lead screw causes the rollers of each pair to come closer or further away from each other.
The machine described in ES 200902283 provided a substantial improvement over the nut peeling devices known in the art at that time. However, although this known peeling machine fully complies with the purpose for which it has been developed, it still suffers from a number of disadvantages. For example, the friction of the rollers on the almonds causes the manufacture material to wear out with time. Additionally, although this known machine includes detectors of such wear, another disadvantage is that the adjustment of the distance between the pressing rollers must be done manually with the help of an external wheel for each pair of rollers.
Therefore, the functional and productive characteristics of the machine described in ES 200902283 may be improved by providing a device that enables a precise adjustment of the working distance between the rollers in the operational range, which may be substantially small, preferably only a few millimeters, and more preferably around 4 mm. For this reason, given the small margin of the working range, a precise positional adjustment of the rollers is required, because a small variation due to the wear of the device or any other circumstance may have a considerable influence on the quality and/or efficiency of the peeling process.